Spiral gearing.



' PATENTED JUNE 11, 1907.

. A. JANSON.

' AL GEARING.

N TILED CARL AUG. JANSION, OF CHICAGO, iLLiNois,

SPIRAL GEARING" Specification of Letters Patent.

Patented June 11, 1907.

Application filed March 14,1906. Serial No. 306.964.

To alt whom it may concern:

Be it known that I, CARL AUGUST J ANSON, a citizen of the United States of America, and a resident of Chicago, in the county of Cook and State of Illino1s, have invented certain new and useful Improvements in Spiral Gearing, of which the following is a specificationl The main object of this invention is to provide an improved form of spiral gearing,

which is particularly adapted'for transmitting-heavy loads with minimum risk of injury to the gearing, which is without blacklash, and in which the strain is spread over a relatively large number of teeth. This object is accomplished by the device shown in the accompanying drawings in which:

Figure 1 is a side elevation partly in section of aform of spiral gearing constructed according to this invention. view of one of the spiral driving members,

showing also a section of the gear wheel, said section being on the line 22 of Fig. 1.

In the construction shown in the draw ings, the wheel 3 is carried by the shaft 4 and the members 5 are rigidly keyed to a shaft 6 which is disposed at right angles to the shaft fl and has its axis in the middle plane of the wheel 3. Each of the members 5 consists of an annular wheel or disk having one ofits side faces adj acentj tothe periphery of the "wheel 3. The opposed faces of the memthe axis of the shaft6.

bers 5 each have an annular surface 7 whose curvature fits the adjacent part of the periphery of the wheel 3. The surface 7 is a surface of revolution such as would be formed by rotating the periphery of the wheel 3 about The surface 7 thus fits the adjacent part of the periphery of the spacing of the successive spirals also conforms with the pitch of the teeth on the gear 3. --The spirals follow the curvature of the surface 7, and are ofuniform transverse section throughout their length, except at Fig. 2 is a face.

the extreme ends where they are preferably rounded ofi. As each spiral exact y fits the space between the adjacent teeth of the wheel 3, there is no backlash. There s no rollin action between the teeth and spirals, and t e pressure is therefore never concentrated on the end of a tooth as in ordinary gearing. Opposite faces of the teeth 9 on the wheel 3 are preferably symmetrical with res ect to each other since the same face of eac tooth has working contact with the convexly curved faces of the spirals on one member 5 and with the concavely curved faces of the spirals on the other member 5.

The members 5 are exactly alike except that they are mounted upon the shafts with their spirally ridged faces opposed to each other and in mesh with opposite sides of the periphery of the wheel 3. Both sets of spirals thus serve to rotate the gear 3 1n the same direction and the pressure is at all'times evenly distributed over eight teeth of the gear 3,-making a structure of great strength. Each spiral, besides following the curvature of the surface 7, is gradually twisted throughout its length so as to exactly conform to the changes of position of the teeth of the gear 3 as the members 5 rotate.

In the operation of the system of gearlng shown, power is transmitted from the shaft 6 to the shaft 4. Like worm earing, thls form of spiral gearing is self-loo 'ng against being driven from the shaft 4.

What I claim as my invention and desire to secure by Letters Patent is: 1. The combination of a wheel having gear teeth on its periphery,a shaft j ournaled on an axis which is at right angles to the axis of said wheel and lies in the plane of said wheel at one side of its axis, two members rigidly mounted on said shaft at opposite sides of said wheel and each having one face adjacent to the periphery of the wheel and having on said face a spiral ridge meshing with the teeth on said wheel, the ridges on said mem-- bers being alike and being adapted to cause said wheel "to rotate through the rotation of said shaft.

2. The combination of a wheel having gear teeth on its periphery, a shaft journaled on an one side of its axis, two members rigidly the pitch of said ridges being a multiple of mounted on said shaft at Opposite sides of the pitch of teeth. 10

said Wheel and each hav ing vone face adja- Signed at Chicago this 8th day of March, cent to the periphery of the wheel and having 1906. w on said face a series of spiral ridges meshing C. AUG. JANSON.

With the teeth 0n -said heel, the ridges on /Vitnessesf v each member being spaced to mesh with the E. A. RUMMLER,

spaces between the teeth of said Wheel and L. A. SMITH. 

